1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Sunplus SoC UART driver 4 * 5 * Author: Hammer Hsieh <hammerh0314@gmail.com> 6 * 7 * Note1: This driver is 8250-like uart, but are not register compatible. 8 * 9 * Note2: On some buses, for preventing data incoherence, must do a read 10 * for ensure write made it to hardware. In this driver, function startup 11 * and shutdown did not do a read but only do a write directly. For what? 12 * In Sunplus bus communication between memory bus and peripheral bus with 13 * posted write, it will send a specific command after last write command 14 * to make sure write done. Then memory bus identify the specific command 15 * and send done signal back to master device. After master device received 16 * done signal, then proceed next write command. It is no need to do a read 17 * before write. 18 */ 19 #include <linux/clk.h> 20 #include <linux/console.h> 21 #include <linux/interrupt.h> 22 #include <linux/io.h> 23 #include <linux/iopoll.h> 24 #include <linux/module.h> 25 #include <linux/of.h> 26 #include <linux/of_platform.h> 27 #include <linux/platform_device.h> 28 #include <linux/reset.h> 29 #include <linux/serial_core.h> 30 #include <linux/serial_reg.h> 31 #include <linux/sysrq.h> 32 #include <linux/tty.h> 33 #include <linux/tty_flip.h> 34 #include <asm/irq.h> 35 36 /* Register offsets */ 37 #define SUP_UART_DATA 0x00 38 #define SUP_UART_LSR 0x04 39 #define SUP_UART_MSR 0x08 40 #define SUP_UART_LCR 0x0C 41 #define SUP_UART_MCR 0x10 42 #define SUP_UART_DIV_L 0x14 43 #define SUP_UART_DIV_H 0x18 44 #define SUP_UART_ISC 0x1C 45 #define SUP_UART_TX_RESIDUE 0x20 46 #define SUP_UART_RX_RESIDUE 0x24 47 48 /* Line Status Register bits */ 49 #define SUP_UART_LSR_BC BIT(5) /* break condition status */ 50 #define SUP_UART_LSR_FE BIT(4) /* frame error status */ 51 #define SUP_UART_LSR_OE BIT(3) /* overrun error status */ 52 #define SUP_UART_LSR_PE BIT(2) /* parity error status */ 53 #define SUP_UART_LSR_RX BIT(1) /* 1: receive fifo not empty */ 54 #define SUP_UART_LSR_TX BIT(0) /* 1: transmit fifo is not full */ 55 #define SUP_UART_LSR_TX_NOT_FULL 1 56 #define SUP_UART_LSR_BRK_ERROR_BITS GENMASK(5, 2) 57 58 /* Line Control Register bits */ 59 #define SUP_UART_LCR_SBC BIT(5) /* select break condition */ 60 61 /* Modem Control Register bits */ 62 #define SUP_UART_MCR_RI BIT(3) /* ring indicator */ 63 #define SUP_UART_MCR_DCD BIT(2) /* data carrier detect */ 64 65 /* Interrupt Status/Control Register bits */ 66 #define SUP_UART_ISC_RXM BIT(5) /* RX interrupt enable */ 67 #define SUP_UART_ISC_TXM BIT(4) /* TX interrupt enable */ 68 #define SUP_UART_ISC_RX BIT(1) /* RX interrupt status */ 69 #define SUP_UART_ISC_TX BIT(0) /* TX interrupt status */ 70 71 #define SUP_DUMMY_READ BIT(16) /* drop bytes received on a !CREAD port */ 72 #define SUP_UART_NR 5 73 74 struct sunplus_uart_port { 75 struct uart_port port; 76 struct clk *clk; 77 struct reset_control *rstc; 78 }; 79 80 static void sp_uart_put_char(struct uart_port *port, unsigned int ch) 81 { 82 writel(ch, port->membase + SUP_UART_DATA); 83 } 84 85 static u32 sunplus_tx_buf_not_full(struct uart_port *port) 86 { 87 unsigned int lsr = readl(port->membase + SUP_UART_LSR); 88 89 return (lsr & SUP_UART_LSR_TX) ? SUP_UART_LSR_TX_NOT_FULL : 0; 90 } 91 92 static unsigned int sunplus_tx_empty(struct uart_port *port) 93 { 94 unsigned int lsr = readl(port->membase + SUP_UART_LSR); 95 96 return (lsr & UART_LSR_TEMT) ? TIOCSER_TEMT : 0; 97 } 98 99 static void sunplus_set_mctrl(struct uart_port *port, unsigned int mctrl) 100 { 101 unsigned int mcr = readl(port->membase + SUP_UART_MCR); 102 103 if (mctrl & TIOCM_DTR) 104 mcr |= UART_MCR_DTR; 105 else 106 mcr &= ~UART_MCR_DTR; 107 108 if (mctrl & TIOCM_RTS) 109 mcr |= UART_MCR_RTS; 110 else 111 mcr &= ~UART_MCR_RTS; 112 113 if (mctrl & TIOCM_CAR) 114 mcr |= SUP_UART_MCR_DCD; 115 else 116 mcr &= ~SUP_UART_MCR_DCD; 117 118 if (mctrl & TIOCM_RI) 119 mcr |= SUP_UART_MCR_RI; 120 else 121 mcr &= ~SUP_UART_MCR_RI; 122 123 if (mctrl & TIOCM_LOOP) 124 mcr |= UART_MCR_LOOP; 125 else 126 mcr &= ~UART_MCR_LOOP; 127 128 writel(mcr, port->membase + SUP_UART_MCR); 129 } 130 131 static unsigned int sunplus_get_mctrl(struct uart_port *port) 132 { 133 unsigned int mcr, ret = 0; 134 135 mcr = readl(port->membase + SUP_UART_MCR); 136 137 if (mcr & UART_MCR_DTR) 138 ret |= TIOCM_DTR; 139 140 if (mcr & UART_MCR_RTS) 141 ret |= TIOCM_RTS; 142 143 if (mcr & SUP_UART_MCR_DCD) 144 ret |= TIOCM_CAR; 145 146 if (mcr & SUP_UART_MCR_RI) 147 ret |= TIOCM_RI; 148 149 if (mcr & UART_MCR_LOOP) 150 ret |= TIOCM_LOOP; 151 152 return ret; 153 } 154 155 static void sunplus_stop_tx(struct uart_port *port) 156 { 157 unsigned int isc; 158 159 isc = readl(port->membase + SUP_UART_ISC); 160 isc &= ~SUP_UART_ISC_TXM; 161 writel(isc, port->membase + SUP_UART_ISC); 162 } 163 164 static void sunplus_start_tx(struct uart_port *port) 165 { 166 unsigned int isc; 167 168 isc = readl(port->membase + SUP_UART_ISC); 169 isc |= SUP_UART_ISC_TXM; 170 writel(isc, port->membase + SUP_UART_ISC); 171 } 172 173 static void sunplus_stop_rx(struct uart_port *port) 174 { 175 unsigned int isc; 176 177 isc = readl(port->membase + SUP_UART_ISC); 178 isc &= ~SUP_UART_ISC_RXM; 179 writel(isc, port->membase + SUP_UART_ISC); 180 } 181 182 static void sunplus_break_ctl(struct uart_port *port, int ctl) 183 { 184 unsigned long flags; 185 unsigned int lcr; 186 187 uart_port_lock_irqsave(port, &flags); 188 189 lcr = readl(port->membase + SUP_UART_LCR); 190 191 if (ctl) 192 lcr |= SUP_UART_LCR_SBC; /* start break */ 193 else 194 lcr &= ~SUP_UART_LCR_SBC; /* stop break */ 195 196 writel(lcr, port->membase + SUP_UART_LCR); 197 198 uart_port_unlock_irqrestore(port, flags); 199 } 200 201 static void transmit_chars(struct uart_port *port) 202 { 203 struct circ_buf *xmit = &port->state->xmit; 204 205 if (port->x_char) { 206 sp_uart_put_char(port, port->x_char); 207 port->icount.tx++; 208 port->x_char = 0; 209 return; 210 } 211 212 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { 213 sunplus_stop_tx(port); 214 return; 215 } 216 217 do { 218 sp_uart_put_char(port, xmit->buf[xmit->tail]); 219 uart_xmit_advance(port, 1); 220 if (uart_circ_empty(xmit)) 221 break; 222 } while (sunplus_tx_buf_not_full(port)); 223 224 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) 225 uart_write_wakeup(port); 226 227 if (uart_circ_empty(xmit)) 228 sunplus_stop_tx(port); 229 } 230 231 static void receive_chars(struct uart_port *port) 232 { 233 unsigned int lsr = readl(port->membase + SUP_UART_LSR); 234 u8 ch, flag; 235 236 do { 237 ch = readl(port->membase + SUP_UART_DATA); 238 flag = TTY_NORMAL; 239 port->icount.rx++; 240 241 if (unlikely(lsr & SUP_UART_LSR_BRK_ERROR_BITS)) { 242 if (lsr & SUP_UART_LSR_BC) { 243 lsr &= ~(SUP_UART_LSR_FE | SUP_UART_LSR_PE); 244 port->icount.brk++; 245 flag = TTY_BREAK; 246 if (uart_handle_break(port)) 247 goto ignore_char; 248 } else if (lsr & SUP_UART_LSR_PE) { 249 port->icount.parity++; 250 flag = TTY_PARITY; 251 } else if (lsr & SUP_UART_LSR_FE) { 252 port->icount.frame++; 253 flag = TTY_FRAME; 254 } 255 256 if (lsr & SUP_UART_LSR_OE) 257 port->icount.overrun++; 258 } 259 260 if (port->ignore_status_mask & SUP_DUMMY_READ) 261 goto ignore_char; 262 263 if (uart_handle_sysrq_char(port, ch)) 264 goto ignore_char; 265 266 uart_insert_char(port, lsr, SUP_UART_LSR_OE, ch, flag); 267 268 ignore_char: 269 lsr = readl(port->membase + SUP_UART_LSR); 270 } while (lsr & SUP_UART_LSR_RX); 271 272 tty_flip_buffer_push(&port->state->port); 273 } 274 275 static irqreturn_t sunplus_uart_irq(int irq, void *args) 276 { 277 struct uart_port *port = args; 278 unsigned int isc; 279 280 uart_port_lock(port); 281 282 isc = readl(port->membase + SUP_UART_ISC); 283 284 if (isc & SUP_UART_ISC_RX) 285 receive_chars(port); 286 287 if (isc & SUP_UART_ISC_TX) 288 transmit_chars(port); 289 290 uart_port_unlock(port); 291 292 return IRQ_HANDLED; 293 } 294 295 static int sunplus_startup(struct uart_port *port) 296 { 297 unsigned long flags; 298 unsigned int isc = 0; 299 int ret; 300 301 ret = request_irq(port->irq, sunplus_uart_irq, 0, "sunplus_uart", port); 302 if (ret) 303 return ret; 304 305 uart_port_lock_irqsave(port, &flags); 306 /* isc define Bit[7:4] int setting, Bit[3:0] int status 307 * isc register will clean Bit[3:0] int status after read 308 * only do a write to Bit[7:4] int setting 309 */ 310 isc |= SUP_UART_ISC_RXM; 311 writel(isc, port->membase + SUP_UART_ISC); 312 uart_port_unlock_irqrestore(port, flags); 313 314 return 0; 315 } 316 317 static void sunplus_shutdown(struct uart_port *port) 318 { 319 unsigned long flags; 320 321 uart_port_lock_irqsave(port, &flags); 322 /* isc define Bit[7:4] int setting, Bit[3:0] int status 323 * isc register will clean Bit[3:0] int status after read 324 * only do a write to Bit[7:4] int setting 325 */ 326 writel(0, port->membase + SUP_UART_ISC); /* disable all interrupt */ 327 uart_port_unlock_irqrestore(port, flags); 328 329 free_irq(port->irq, port); 330 } 331 332 static void sunplus_set_termios(struct uart_port *port, 333 struct ktermios *termios, 334 const struct ktermios *oldtermios) 335 { 336 u32 ext, div, div_l, div_h, baud, lcr; 337 u32 clk = port->uartclk; 338 unsigned long flags; 339 340 baud = uart_get_baud_rate(port, termios, oldtermios, 0, port->uartclk / 16); 341 342 /* baud rate = uartclk / ((16 * divisor + 1) + divisor_ext) */ 343 clk += baud >> 1; 344 div = clk / baud; 345 ext = div & 0x0F; 346 div = (div >> 4) - 1; 347 div_l = (div & 0xFF) | (ext << 12); 348 div_h = div >> 8; 349 350 switch (termios->c_cflag & CSIZE) { 351 case CS5: 352 lcr = UART_LCR_WLEN5; 353 break; 354 case CS6: 355 lcr = UART_LCR_WLEN6; 356 break; 357 case CS7: 358 lcr = UART_LCR_WLEN7; 359 break; 360 default: 361 lcr = UART_LCR_WLEN8; 362 break; 363 } 364 365 if (termios->c_cflag & CSTOPB) 366 lcr |= UART_LCR_STOP; 367 368 if (termios->c_cflag & PARENB) { 369 lcr |= UART_LCR_PARITY; 370 371 if (!(termios->c_cflag & PARODD)) 372 lcr |= UART_LCR_EPAR; 373 } 374 375 uart_port_lock_irqsave(port, &flags); 376 377 uart_update_timeout(port, termios->c_cflag, baud); 378 379 port->read_status_mask = 0; 380 if (termios->c_iflag & INPCK) 381 port->read_status_mask |= SUP_UART_LSR_PE | SUP_UART_LSR_FE; 382 383 if (termios->c_iflag & (BRKINT | PARMRK)) 384 port->read_status_mask |= SUP_UART_LSR_BC; 385 386 /* Characters to ignore */ 387 port->ignore_status_mask = 0; 388 if (termios->c_iflag & IGNPAR) 389 port->ignore_status_mask |= SUP_UART_LSR_FE | SUP_UART_LSR_PE; 390 391 if (termios->c_iflag & IGNBRK) { 392 port->ignore_status_mask |= SUP_UART_LSR_BC; 393 394 if (termios->c_iflag & IGNPAR) 395 port->ignore_status_mask |= SUP_UART_LSR_OE; 396 } 397 398 /* Ignore all characters if CREAD is not set */ 399 if ((termios->c_cflag & CREAD) == 0) { 400 port->ignore_status_mask |= SUP_DUMMY_READ; 401 /* flush rx data FIFO */ 402 writel(0, port->membase + SUP_UART_RX_RESIDUE); 403 } 404 405 /* Settings for baud rate divisor and lcr */ 406 writel(div_h, port->membase + SUP_UART_DIV_H); 407 writel(div_l, port->membase + SUP_UART_DIV_L); 408 writel(lcr, port->membase + SUP_UART_LCR); 409 410 uart_port_unlock_irqrestore(port, flags); 411 } 412 413 static void sunplus_set_ldisc(struct uart_port *port, struct ktermios *termios) 414 { 415 int new = termios->c_line; 416 417 if (new == N_PPS) 418 port->flags |= UPF_HARDPPS_CD; 419 else 420 port->flags &= ~UPF_HARDPPS_CD; 421 } 422 423 static const char *sunplus_type(struct uart_port *port) 424 { 425 return port->type == PORT_SUNPLUS ? "sunplus_uart" : NULL; 426 } 427 428 static void sunplus_config_port(struct uart_port *port, int type) 429 { 430 if (type & UART_CONFIG_TYPE) 431 port->type = PORT_SUNPLUS; 432 } 433 434 static int sunplus_verify_port(struct uart_port *port, struct serial_struct *ser) 435 { 436 if (ser->type != PORT_UNKNOWN && ser->type != PORT_SUNPLUS) 437 return -EINVAL; 438 439 return 0; 440 } 441 442 #if defined(CONFIG_SERIAL_SUNPLUS_CONSOLE) || defined(CONFIG_CONSOLE_POLL) 443 static void wait_for_xmitr(struct uart_port *port) 444 { 445 unsigned int val; 446 int ret; 447 448 /* Wait while FIFO is full or timeout */ 449 ret = readl_poll_timeout_atomic(port->membase + SUP_UART_LSR, val, 450 (val & SUP_UART_LSR_TX), 1, 10000); 451 452 if (ret == -ETIMEDOUT) { 453 dev_err(port->dev, "Timeout waiting while UART TX FULL\n"); 454 return; 455 } 456 } 457 #endif 458 459 #ifdef CONFIG_CONSOLE_POLL 460 static void sunplus_poll_put_char(struct uart_port *port, unsigned char data) 461 { 462 wait_for_xmitr(port); 463 sp_uart_put_char(port, data); 464 } 465 466 static int sunplus_poll_get_char(struct uart_port *port) 467 { 468 unsigned int lsr = readl(port->membase + SUP_UART_LSR); 469 470 if (!(lsr & SUP_UART_LSR_RX)) 471 return NO_POLL_CHAR; 472 473 return readl(port->membase + SUP_UART_DATA); 474 } 475 #endif 476 477 static const struct uart_ops sunplus_uart_ops = { 478 .tx_empty = sunplus_tx_empty, 479 .set_mctrl = sunplus_set_mctrl, 480 .get_mctrl = sunplus_get_mctrl, 481 .stop_tx = sunplus_stop_tx, 482 .start_tx = sunplus_start_tx, 483 .stop_rx = sunplus_stop_rx, 484 .break_ctl = sunplus_break_ctl, 485 .startup = sunplus_startup, 486 .shutdown = sunplus_shutdown, 487 .set_termios = sunplus_set_termios, 488 .set_ldisc = sunplus_set_ldisc, 489 .type = sunplus_type, 490 .config_port = sunplus_config_port, 491 .verify_port = sunplus_verify_port, 492 #ifdef CONFIG_CONSOLE_POLL 493 .poll_put_char = sunplus_poll_put_char, 494 .poll_get_char = sunplus_poll_get_char, 495 #endif 496 }; 497 498 #ifdef CONFIG_SERIAL_SUNPLUS_CONSOLE 499 static struct sunplus_uart_port *sunplus_console_ports[SUP_UART_NR]; 500 501 static void sunplus_uart_console_putchar(struct uart_port *port, 502 unsigned char ch) 503 { 504 wait_for_xmitr(port); 505 sp_uart_put_char(port, ch); 506 } 507 508 static void sunplus_console_write(struct console *co, 509 const char *s, 510 unsigned int count) 511 { 512 unsigned long flags; 513 int locked = 1; 514 515 local_irq_save(flags); 516 517 if (sunplus_console_ports[co->index]->port.sysrq) 518 locked = 0; 519 else if (oops_in_progress) 520 locked = uart_port_trylock(&sunplus_console_ports[co->index]->port); 521 else 522 uart_port_lock(&sunplus_console_ports[co->index]->port); 523 524 uart_console_write(&sunplus_console_ports[co->index]->port, s, count, 525 sunplus_uart_console_putchar); 526 527 if (locked) 528 uart_port_unlock(&sunplus_console_ports[co->index]->port); 529 530 local_irq_restore(flags); 531 } 532 533 static int __init sunplus_console_setup(struct console *co, char *options) 534 { 535 struct sunplus_uart_port *sup; 536 int baud = 115200; 537 int bits = 8; 538 int parity = 'n'; 539 int flow = 'n'; 540 541 if (co->index < 0 || co->index >= SUP_UART_NR) 542 return -EINVAL; 543 544 sup = sunplus_console_ports[co->index]; 545 if (!sup) 546 return -ENODEV; 547 548 if (options) 549 uart_parse_options(options, &baud, &parity, &bits, &flow); 550 551 return uart_set_options(&sup->port, co, baud, parity, bits, flow); 552 } 553 554 static struct uart_driver sunplus_uart_driver; 555 static struct console sunplus_uart_console = { 556 .name = "ttySUP", 557 .write = sunplus_console_write, 558 .device = uart_console_device, 559 .setup = sunplus_console_setup, 560 .flags = CON_PRINTBUFFER, 561 .index = -1, 562 .data = &sunplus_uart_driver 563 }; 564 565 #define SERIAL_SUNPLUS_CONSOLE (&sunplus_uart_console) 566 #else 567 #define SERIAL_SUNPLUS_CONSOLE NULL 568 #endif 569 570 static struct uart_driver sunplus_uart_driver = { 571 .owner = THIS_MODULE, 572 .driver_name = "sunplus_uart", 573 .dev_name = "ttySUP", 574 .major = TTY_MAJOR, 575 .minor = 64, 576 .nr = SUP_UART_NR, 577 .cons = SERIAL_SUNPLUS_CONSOLE, 578 }; 579 580 static void sunplus_uart_disable_unprepare(void *data) 581 { 582 clk_disable_unprepare(data); 583 } 584 585 static void sunplus_uart_reset_control_assert(void *data) 586 { 587 reset_control_assert(data); 588 } 589 590 static int sunplus_uart_probe(struct platform_device *pdev) 591 { 592 struct sunplus_uart_port *sup; 593 struct uart_port *port; 594 struct resource *res; 595 int ret, irq; 596 597 pdev->id = of_alias_get_id(pdev->dev.of_node, "serial"); 598 599 if (pdev->id < 0 || pdev->id >= SUP_UART_NR) 600 return -EINVAL; 601 602 sup = devm_kzalloc(&pdev->dev, sizeof(*sup), GFP_KERNEL); 603 if (!sup) 604 return -ENOMEM; 605 606 sup->clk = devm_clk_get_optional(&pdev->dev, NULL); 607 if (IS_ERR(sup->clk)) 608 return dev_err_probe(&pdev->dev, PTR_ERR(sup->clk), "clk not found\n"); 609 610 ret = clk_prepare_enable(sup->clk); 611 if (ret) 612 return ret; 613 614 ret = devm_add_action_or_reset(&pdev->dev, sunplus_uart_disable_unprepare, sup->clk); 615 if (ret) 616 return ret; 617 618 sup->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL); 619 if (IS_ERR(sup->rstc)) 620 return dev_err_probe(&pdev->dev, PTR_ERR(sup->rstc), "rstc not found\n"); 621 622 port = &sup->port; 623 624 port->membase = devm_platform_get_and_ioremap_resource(pdev, 0, &res); 625 if (IS_ERR(port->membase)) 626 return dev_err_probe(&pdev->dev, PTR_ERR(port->membase), "membase not found\n"); 627 628 irq = platform_get_irq(pdev, 0); 629 if (irq < 0) 630 return irq; 631 632 port->mapbase = res->start; 633 port->uartclk = clk_get_rate(sup->clk); 634 port->line = pdev->id; 635 port->irq = irq; 636 port->dev = &pdev->dev; 637 port->iotype = UPIO_MEM; 638 port->ops = &sunplus_uart_ops; 639 port->flags = UPF_BOOT_AUTOCONF; 640 port->fifosize = 128; 641 642 ret = reset_control_deassert(sup->rstc); 643 if (ret) 644 return ret; 645 646 ret = devm_add_action_or_reset(&pdev->dev, sunplus_uart_reset_control_assert, sup->rstc); 647 if (ret) 648 return ret; 649 650 #ifdef CONFIG_SERIAL_SUNPLUS_CONSOLE 651 sunplus_console_ports[sup->port.line] = sup; 652 #endif 653 654 platform_set_drvdata(pdev, &sup->port); 655 656 ret = uart_add_one_port(&sunplus_uart_driver, &sup->port); 657 #ifdef CONFIG_SERIAL_SUNPLUS_CONSOLE 658 if (ret) 659 sunplus_console_ports[sup->port.line] = NULL; 660 #endif 661 662 return ret; 663 } 664 665 static int sunplus_uart_remove(struct platform_device *pdev) 666 { 667 struct sunplus_uart_port *sup = platform_get_drvdata(pdev); 668 669 uart_remove_one_port(&sunplus_uart_driver, &sup->port); 670 671 return 0; 672 } 673 674 static int __maybe_unused sunplus_uart_suspend(struct device *dev) 675 { 676 struct sunplus_uart_port *sup = dev_get_drvdata(dev); 677 678 if (!uart_console(&sup->port)) 679 uart_suspend_port(&sunplus_uart_driver, &sup->port); 680 681 return 0; 682 } 683 684 static int __maybe_unused sunplus_uart_resume(struct device *dev) 685 { 686 struct sunplus_uart_port *sup = dev_get_drvdata(dev); 687 688 if (!uart_console(&sup->port)) 689 uart_resume_port(&sunplus_uart_driver, &sup->port); 690 691 return 0; 692 } 693 694 static const struct dev_pm_ops sunplus_uart_pm_ops = { 695 SET_SYSTEM_SLEEP_PM_OPS(sunplus_uart_suspend, sunplus_uart_resume) 696 }; 697 698 static const struct of_device_id sp_uart_of_match[] = { 699 { .compatible = "sunplus,sp7021-uart" }, 700 {} 701 }; 702 MODULE_DEVICE_TABLE(of, sp_uart_of_match); 703 704 static struct platform_driver sunplus_uart_platform_driver = { 705 .probe = sunplus_uart_probe, 706 .remove = sunplus_uart_remove, 707 .driver = { 708 .name = "sunplus_uart", 709 .of_match_table = sp_uart_of_match, 710 .pm = &sunplus_uart_pm_ops, 711 } 712 }; 713 714 static int __init sunplus_uart_init(void) 715 { 716 int ret; 717 718 ret = uart_register_driver(&sunplus_uart_driver); 719 if (ret) 720 return ret; 721 722 ret = platform_driver_register(&sunplus_uart_platform_driver); 723 if (ret) 724 uart_unregister_driver(&sunplus_uart_driver); 725 726 return ret; 727 } 728 module_init(sunplus_uart_init); 729 730 static void __exit sunplus_uart_exit(void) 731 { 732 platform_driver_unregister(&sunplus_uart_platform_driver); 733 uart_unregister_driver(&sunplus_uart_driver); 734 } 735 module_exit(sunplus_uart_exit); 736 737 #ifdef CONFIG_SERIAL_EARLYCON 738 static void sunplus_uart_putc(struct uart_port *port, unsigned char c) 739 { 740 unsigned int val; 741 int ret; 742 743 ret = readl_poll_timeout_atomic(port->membase + SUP_UART_LSR, val, 744 (val & UART_LSR_TEMT), 1, 10000); 745 if (ret) 746 return; 747 748 writel(c, port->membase + SUP_UART_DATA); 749 } 750 751 static void sunplus_uart_early_write(struct console *con, const char *s, unsigned int n) 752 { 753 struct earlycon_device *dev = con->data; 754 755 uart_console_write(&dev->port, s, n, sunplus_uart_putc); 756 } 757 758 static int __init 759 sunplus_uart_early_setup(struct earlycon_device *dev, const char *opt) 760 { 761 if (!(dev->port.membase || dev->port.iobase)) 762 return -ENODEV; 763 764 dev->con->write = sunplus_uart_early_write; 765 766 return 0; 767 } 768 OF_EARLYCON_DECLARE(sunplus_uart, "sunplus,sp7021-uart", sunplus_uart_early_setup); 769 #endif 770 771 MODULE_DESCRIPTION("Sunplus UART driver"); 772 MODULE_AUTHOR("Hammer Hsieh <hammerh0314@gmail.com>"); 773 MODULE_LICENSE("GPL v2"); 774